The woman, who did not want to be named, said she saw tyre marks swerving back and forth on Massey Rd heading in the direction of Buckland Rd.
"There were tire zig zags all over the road, single tyre marks...as if he was weaving in and out of traffic."
The road would have been reasonably busy at the time of the chase, she said.
When she got to the intersection of Massey and Buckland roads it was blocked by several police cars. A policeman near the crash told her the road was a crime scene and a man was dead or dying.
Police said in a statement that they had attempted to pull over a motorcyclist who was speeding on Massey Rd around 7.20pm.
"The driver failed to stop and police initiated a pursuit. Almost immediately after this the motorcyclist has crashed near the intersection with Royton Avenue," police said.
"Unfortunately the man has died at the scene."
No one else was injured in the crash.
A police spokeswoman confirmed a police motorbike had been involved in the chase.
A woman, who asked to stay anonymous, said she saw a police motorbike in pursuit of the motorcyclist while she was at the Massey Rd BP station, which is 1.2km from Buckland Rd.
"I stopped my car to let the motorcyclist and police through as the motorcyclist wasn't stopping at all," she said.
"The person was driving at an increasingly high speed - the cops were struggling to keep up. The cop on the motorbike was about five seconds behind him, then another police [vehicle] came from Vine St a few seconds behind the police motorcyclist."
Texts from her phone show the pursuit went past some time between 7.17pm and 7.20pm, she said.
Buckland Rd is now closed between Massey Rd and Ashley Ave. A local resident said earlier she could see what appeared to be a body covered in a white cloth on the road. The street was full of police cars.
Northern fire service shift manager Megan Ruru said the fire service had been called to the incident at 7.35pm. She said she was unable to comment further.
Police said the road will remain closed until 2am while the Serious Crash Unit investigates, and motorists are asked to avoid the area.
The Independent Police Conduct Authority has also been notified.
